Last week in Tackling Climate Change we took a reality check on the level of challenge embodied in established targets for reducing emissions of the greenhouse gas carbon dioxide.

This week, we're announcing a new call to action for architecture firms across the United States and Europe and around the world.

Last week we also reviewed some of the reasons to suspect that established emissions targets for 2020 and 2050 are likely to prove too slack, relative to the sensitivity of Earth's climate systems, rather than too stringent. And we recalled that the best available economic studies of climate change show very large costs, which can still be avoided by timely and large but cost-effective investments in emissions reductions.

It is important to start this call to action by recognizing that great efforts are already underway, involving tens of thousands of design professionals, in most countries of the world. Any constructive call for more must be entirely additive to these large, impressive, and growing programs.

LEED and Energy Star

For the United States, the Leadership in Energy and Environmental Design (LEED) Green Building Rating System administered by the non-profit U.S. Green Building Council (USGBC) is an outstanding set of programs that are helping to make a real difference.

LEED provides the essential rigor of third-party verification, and while it is not a perfect system, it seems, especially at the Gold and Platinum levels of certification, to have been effectively calibrated to drive significant improvements in the construction of buildings and their impacts.

Two key statistics about LEED adoption are very telling. Nearly fifty thousand design professionals have gotten training and passed exams to formally add LEED to their professional credentials. It's an impressive level of involvement that suggests the program is broad and accessible, and that it is having an extensive impact on a professional culture that is hungry for it.

At the same time, the total number of actually constructed LEED-certified buildings is fewer than two thousand, while the total number of LEED Platinum-certified buildings is less than 100.
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